SELECT 
  1 
FROM 
  cscart_multi_declock_keys 
WHERE 
  key_id = '7ed45070ad3e8feb608eba3382f6b7ef8e2d8bb5bb4098a2cb93e2491c06bb14' 
  AND token = 'ult9/boFgWh3jwjOZHoKK2F+pCHZthYa8VQYLdNgNZg=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00019

JSON explain

{
  "query_block": {
    "select_id": 1,
    "message": "no matching row in const table"
  }
}